Cretaceous-origin
Guides
Amblyoponinae
Dracula ants, Vampire ants
Amblyoponinae is an ancient, relictual subfamily of ants characterized by specialized subterranean predatory habits and unique 'Dracula ant' behavior, in which adult workers pierce the integument of their own larvae to imbibe haemolymph. The subfamily contains 13 extant genera and originated in the mid-Cretaceous approximately 107 million years ago. Crown group diversification occurred in the Late Paleocene/Early Eocene. The subfamily exhibits remarkable morphological and behavioral diversity, including convergent evolution of army ant-like behaviors in some lineages and highly plastic caste systems in others.
Embolemus
Embolemus is a genus of small parasitoid wasps in the family Embolemidae, first described by Westwood in 1833. The genus contains approximately 32 extant species and numerous fossil species preserved in amber deposits from the Cretaceous and Eocene periods. Taxonomic debate persists regarding the status of Ampulicomorpha, which most authorities now treat as a junior synonym of Embolemus. The genus has a cosmopolitan distribution, with records from Europe, Asia, and other regions.
Evaniidae
ensign wasps, nightshade wasps, hatchet wasps, cockroach egg parasitoid wasps
Evaniidae is a family of solitary parasitoid wasps commonly known as ensign wasps, nightshade wasps, or hatchet wasps. The family comprises approximately 20 extant genera containing over 400 described species, with a nearly cosmopolitan distribution excluding polar regions. Evaniidae are immediately distinctive among Hymenoptera due to their unique morphology: the metasoma (abdomen) is attached very high on the propodeum, well above the hind coxae, and is connected by a long, one-segmented, tube-like petiole. The common name "ensign wasp" derives from the characteristic habit of these wasps to jerk their small, flag-like metasoma up and down while walking. All known evaniid larvae are specialized parasitoids that develop inside the egg cases (oothecae) of cockroaches (Blattodea), consuming the host eggs.
Megophthalminae
Megophthalminae is a subfamily of leafhoppers (Cicadellidae) established by Kirkaldy in 1906. It was historically treated as a separate family or as the subfamily Agalliinae, but phylogenetic analyses have confirmed its placement within Cicadellidae. The subfamily includes four tribes: Adelungiini, Agalliini, Megophthalmini, and Evansiolini. Members are characterized by morphological convergence with treehoppers (Membracoidea), particularly in ocelli and wing modifications. The group originated in the early Cretaceous (~140 million years ago) and shows strong continental-scale biogeographic structure.
Ochrotrichiinae
microcaddisflies
Ochrotrichiinae is a subfamily of microcaddisflies within the family Hydroptilidae, comprising approximately 430 species across nine genera. The subfamily is most diverse in the Neotropics, with additional representation in the Nearctic and Australasian regions, including an endemic genus in New Caledonia. Phylogenetic analyses support its monophyly with the exclusion of Dibusa. The subfamily originated in the New World during the early Cretaceous, approximately 116 million years ago, with subsequent dispersal to Australasia via trans-Antarctic routes.
Pleocoma
rain beetles
Pleocoma is the sole extant genus of Pleocomidae, a family endemic to the Pacific states of North America. These beetles are notable for their extreme subterranean lifestyle, with adults emerging only during fall and winter rains to mate. The genus name derives from Greek words for 'abundant hair,' referring to the dense ventral hair covering. Adults are non-feeding, while larvae are root-feeders with exceptionally long development periods of up to 13 years.
Scarabaeoidearain-beetlessubterraneannon-feeding-adultslong-lived-larvaepheromone-mediated-matingendemicNearcticrelictual-distributionCretaceous-originpest-of-Christmas-treeslamellate-antennaeflightless-femalesrain-triggered-emergenceCalifornia-faunaOregon-faunaWashington-faunaroot-feeding-larvaeextreme-seasonalitylight-attracted-malesPseudomyrmecinae
big-eyed tree ants, big-eyed ants
Pseudomyrmecinae is a subfamily of slender, hyperoptic arboreal ants comprising three genera: Pseudomyrmex (~200 species, Neotropical), Tetraponera (~100 species, Palaeotropical), and Myrcidris (two species, South America). The subfamily originated in the Palaeotropics during the Cretaceous and later dispersed to South America, where it underwent significant diversification. At least twelve independent origins of obligate mutualisms with domatia-bearing plants have occurred within this group, making it the most diverse plant-occupying ant lineage worldwide.
Pseudopsinae
Pseudopsinae is a small subfamily of rove beetles (Staphylinidae) containing four extant genera—Pseudopsis, Nanobius, Asemobius, and Zalobius—with approximately 55 species. The subfamily is distinguished by longitudinal carinae on the head, pronotum, and elytra, and a fine stridulatory file on the genital segment. Fossil records extend to the Lower Cretaceous (~125 Ma), indicating an ancient origin. Members inhabit moist microhabitats including forest leaf litter, fungi, and riparian moss.
Sasajiscymnus
Sasajiscymnus is a genus of small lady beetles (Coccinellidae) established by Vandenberg in 2004. The genus contains over 100 species distributed across Asia, Africa, and Oceania. Molecular evidence suggests an origin in the Late Cretaceous, approximately 78 million years ago. The genus includes S. tsugae, which has been widely studied and deployed as a biological control agent against the hemlock woolly adelgid in North America.
Scarabaeinae
true dung beetles, dung beetles
Scarabaeinae is a subfamily of scarab beetles comprising the true dung beetles. Adults typically feed on dung, though some species consume carrion, decaying fruit, or fungi. The subfamily is divided into three functional guilds—rollers (telecoprids), tunnelers (paracoprids), and dwellers (endocoprids)—based on dung processing behavior. Members exhibit modified mouthparts with an expanded clypeus covering the mandibles, and possess a space between the middle legs for dung manipulation. The subfamily originated in the Lower Cretaceous (115–130 million years ago) and is hypothesized to have co-evolved with dinosaurs.